Fault-tolerant Enterprise Object Storage System for Small Objects

ABSTRACT

Various implementations disclosed herein provide fault-tolerant enterprise object storage system that can store small objects. In various implementations, the fault-tolerant enterprise object storage system writes a small object into an aggregate object that is distributed across a plurality of storage entities. In some implementations, the small object is at least an order of magnitude smaller than the aggregate object, and the small object is within the same order of magnitude of a block unit addressable within each of the storage entities. In some implementations, based on the small object, the storage system updates the parity data associated with the aggregate object in response to writing the small object into the aggregate object. In various implementations, the storage system updates a processed data end offset indicator that indicates that the parity data for the aggregate object includes valid data up to and including the small object.

TECHNICAL FIELD

The present disclosure generally relates to enterprise storage systems,and in particular, to a fault-tolerant enterprise object storage systemfor small objects.

BACKGROUND

An enterprise storage system (“storage system,” hereinafter) typicallyincludes various storage entities provided to store data associated withobjects. A storage entity often includes various addressable datablocks. A data block usually refers to the smallest addressable block ofmemory in a storage entity that stores the data associated with theobjects. The average size of a typical object is sometimes an order ofmagnitude larger than the size of a data block. As such, most previouslyavailable storage systems store the object using numerous data blocksacross multiple storage entities. Such storage systems are typicallyinefficient at storing objects that are less than or of the same orderof magnitude as the size of a data block.

Some storage systems also provide fault-tolerance. Such storage systemsare usually able to recover an object when there is a need to recoverthe object. For example, previously available storage systems typicallyrecover an object in response to detecting a loss of data at a storageentity that stored data associated with the object. Prior storagesystems use parity data for an object to recover the object. The paritydata is typically stored in parity blocks across multiple storageentities. A parity block usually refers to the smallest addressableblock of memory in a storage entity that stores the parity data. Somepreviously available storage systems are inefficient at storage spaceutilization because they use more parity blocks than needed to providefault tolerance.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the present disclosure can be understood by those of ordinaryskill in the art, a more detailed description may be had by reference toaspects of some illustrative implementations, some of which are shown inthe accompanying drawings.

FIG. 1 is a schematic diagram of an enterprise storage systemenvironment in accordance with some implementations.

FIG. 2 is a block diagram of an enterprise storage system in accordancewith some implementations.

FIG. 3A is a flowchart representation of a method of writing smallobjects in the enterprise storage system in accordance with someimplementations.

FIG. 3B is a flowchart representation of another method of writing smallobjects in the enterprise storage system in accordance with someimplementations.

FIG. 4A is a flowchart representation of a method of recovering smallobjects upon detecting a loss of data at a storage entity in accordancewith some implementations.

FIG. 4B is a flowchart representation of a method of determining whetherthe parity data associated with an aggregate object includes valid datafor small objects in accordance with some implementations.

FIG. 5A is a flowchart representation of a method of deleting smallobjects from the enterprise storage system in accordance with someimplementations.

FIG. 5B is a flowchart representation of a method of compacting anaggregate object in accordance with some implementations.

FIG. 6 is a diagram that illustrates small objects being written intothe enterprise storage system in accordance with some implementations.

FIG. 7 is another diagram that illustrates small objects being writteninto the enterprise storage system in accordance with someimplementations.

FIG. 8 is a block diagram of a server system enabled with variousmodules that facilitate the writing, recovering, and/or deleting ofsmall objects in accordance with some implementations.

In accordance with common practice the various features illustrated inthe drawings may not be drawn to scale. Accordingly, the dimensions ofthe various features may be arbitrarily expanded or reduced for clarity.In addition, some of the drawings may not depict all of the componentsof a given system, method or device. Finally, like reference numeralsmay be used to denote like features throughout the specification andfigures.

DESCRIPTION OF EXAMPLE EMBODIMENTS

Numerous details are described in order to provide a thoroughunderstanding of the example implementations shown in the drawings.However, the drawings merely show some example aspects of the presentdisclosure and are therefore not to be considered limiting. Those ofordinary skill in the art will appreciate that other effective aspectsand/or variants do not include all of the specific details describedherein. Moreover, well-known systems, methods, components, devices andcircuits have not been described in exhaustive detail so as not toobscure more pertinent aspects of the example implementations describedherein.

Overview

Some previously available fault-tolerant enterprise object storagesystems (storage system, hereinafter) are configured to store largeobjects. A large object typically refers to an object that is at leastan order of magnitude larger than the smallest addressable block ofmemory (e.g., allocation unit of data) in the storage system. As such,in some previously available storage systems, the parity data for asmall object typically occupies the same amount of space on disk thanthe size of the small object because of the method of error controlcoding utilized and reduces the benefits of erasure coding. A smallobject refers to an object that is typically less than or about the samesize as the smallest addressable block of memory in the storage system.Hence, some previously available storage systems are not efficient atstoring small objects. Moreover, some previously available storagesystems do not synthesize parity data for small objects upon receivingthe small objects. Hence, some previously available storage systems arenot capable of recovering a small object in the event of a data lossbecause there is typically no parity data for the small object.

By contrast, various implementations disclosed herein enable writingsmall objects into a fault-tolerant enterprise object storage systemthat stores the small objects in a relatively efficient manner andrecovers the small objects in the event of a data loss. For example, invarious implementations, a method of writing a small object is performedby a fault-tolerant enterprise object storage system that is configuredto synthesize parity data in order to protect stored data from loss.Hereinafter, the fault-tolerant enterprise object storage system isreferred to as a storage system. In various implementations, the storagesystem includes a plurality of storage entities that are configured tostore data on a block basis. In various implementations, the storagesystem includes one or more processors. In various implementations, themethod includes writing a first object (e.g., a small object) into anaggregate object that is distributed across the plurality of storageentities. In some implementations, a first size of the first object isat least an order of magnitude less than a second size of the aggregateobject and within the same order of magnitude of a block unitaddressable within each of the storage entities. In variousimplementations, the method includes updating, based on the firstobject, parity data associated with the aggregate object in response towriting the first object into the aggregate object. The parityinformation is stored at one or more parity storage entities. In variousimplementations, the method also includes updating a processed data endoffset indicator that indicates that the parity data for the aggregateobject includes valid data up to and including the first object.

FIG. 1 is a block diagram of a storage system environment 10 inaccordance with some implementations. While pertinent features areshown, those of ordinary skill in the art will appreciate from thepresent disclosure that various other features have not been illustratedfor the sake of brevity and so as not to obscure more pertinent aspectsof the example implementations disclosed herein. To that end, as anon-limiting example, the storage system environment 10 includes one ormore client devices 20, a network 30 (e.g., a public/external networksuch as the Internet), and a fault-tolerant enterprise object storagesystem 100 (storage system 100, hereinafter).

In operation, the storage system 100 is utilized to store variousobjects. In some implementations, an object refers to any data asset. Insome implementations, an object includes a data asset that ispresentable to a user via the client device 20. For example, the objectincludes a video file that represents a movie, an audio file thatrepresents a song, a text file, etc. More generally, in variousimplementations, the object includes a file of any file type (e.g.,.mov, .wma, .mp4, .avi, .mp3, .jpg, .txt, .doc, .docx, .xls, .ppt, etc.)In some implementations, an object includes a data asset that representsa set of computer-readable instructions that are executable at theclient device 20. For example, in some implementations, the objectincludes a native application that is downloaded and installed at theclient device 20, a browser plugin, etc.

In various implementations, the storage system 100 includes one or moredata storage entities 110, one or more parity storage entities 120, andan ingest entity 130. The data storage entities 110 store dataassociated with the objects. Hereinafter, the data associated with anobject is referred to as object data. In some implementations, a datastorage entity 110 includes one or more computer readable storagemediums. For example, the data storage entity 110 includes solid statememory devices, hard disk memory devices, optical disk drives, read-onlymemory and/or nanotube-based storage devices. In some implementations,the data storage entities 110 includes data servers that executecomputer-readable instructions. In various implementations, a datastorage entity 110 includes various data blocks (not shown) for storingobject data. As described herein, in various implementations, a datablock refers to the smallest addressable block of memory (e.g., thesmallest allocation unit of data) in a data storage entity 110. In someimplementations, the data blocks are identically-sized (e.g., 2 MBeach).

In various implementations, the parity storage entities 120 store paritydata associated with the objects. In some implementations, the storagesystem 100 synthesizes parity data for an object, and stores the paritydata in the parity storage entities 120. The storage system 100 utilizesany suitable technique for synthesizing the parity data. In variousimplementations, the storage system 100 utilizes the parity data for anobject to recover the object in the event of a data loss at a datastorage entity 110. In some implementations, recovering an object refersto rebuilding, reconstructing, restoring, and/or repairing the object.For example, if a data storage entity 110 that stores a portion of theobject data crashes, then the storage system 100 utilizes the paritydata to recover the object. The storage system 100 utilizes any suitabletechnique for recovering the object. Similar to the data storageentities 110, in some implementations, the parity storage entities 120include one or more computer readable mediums for storing the paritydata. In various implementations, a parity storage entity 120 includesvarious parity blocks (not shown) for storing parity data. In someimplementations, a parity block refers to the smallest addressable blockof memory (e.g., the smallest allocation unit of data) in a paritystorage entity 120. In some implementations, the parity blocks areidentically-sized (e.g., 2 MB each).

In various implementations, the ingest entity 130 serves as an interfacefor the storage system 100. The ingest entity 130 receives/transmitsdata from/to any device that is external to the storage system 100.Specifically, the ingest entity 130 receives/transmits data from/to theclient devices 20. In various implementations, receiving/transmittingdata includes receiving/transmitting the objects. Alternatively oradditionally, receiving/transmitting data includesreceiving/transmitting instructions. In some implementations, theinstructions include operations that are performed in relation to theobjects. Example instructions include writing an object, reading anobject, deleting an object, copying an object, etc. In someimplementations, the ingest entity 130 includes hardware and/or softwarethat enables the ingest entity 130 to perform its functionality. In someexamples, the ingest entity 130 is implemented by a server system (e.g.,as described in FIG. 8).

In various implementations, the storage system 100 utilizes varioustechniques associated with distributed erasure coding. In someimplementations, the storage system 100 distributes an object acrossmultiple (e.g., all) data storage entities 110. For example, the storagesystem 100 stores the first 2 MB of the object data at one data storageentity 110, the next 2 MB of the object data at another data storageentity 110, etc. In some implementations, the storage system 100distributes the object across multiple data storage entities 110 even ifthe object is small enough to be stored at a single data storage entity110. Distributing the object data across multiple data storage entities110 reduces the risk of losing object data for the entire object.Similarly, in some implementations, the storage system 100 distributesthe parity data for an object across multiple (e.g., all) parity storageentities 120.

In some implementations, the storage system 100 (e.g., the ingest entity130) receives a write request 148 from the client device 20. The writerequest 148 includes a request to write (e.g., store) a small object 150into the storage system 100. In some implementations, the write request148 includes the small object 150. Alternatively or additionally, thewrite request 148 includes an object identifier (e.g., a UniformResource Identifier (URI)) and/or a link (e.g., a Uniform ResourceLocator (URL)) that the storage system 100 utilizes to fetch the smallobject 150. In some implementations, a small object 150 refers to anobject that is smaller than or about the same size as the data blocksand/or the parity blocks. In other words, in some implementations, asmall object 150 refers to an object that is less than, or of the sameorder of magnitude as the data block and/or the parity block.

In various implementations, the ingest entity 130 writes the smallobject 150 into an aggregate object 170 that is stored across multipledata storage entities 110. In some implementations, the aggregate object170 refers to a relatively large object that occupies a set of datablocks across multiple data storage entities 110. In suchimplementations, the ingest entity 130 writes the small object 150 intothe aggregate object 170 by writing the object data for the small object150 into one or more of the data blocks that the aggregate object 170occupies. In some implementations, the aggregate object 170 refers to acollection of objects. In such implementations, the ingest entity 130writes the small object 150 to the aggregate object 170 by including thesmall object 150 in the collection. In various implementations, theaggregate object 170 is at least an order of magnitude larger than thesmall object 150.

In various implementations, the ingest entity 130 synthesizes paritydata for the small object 150. The ingest entity 130 utilizes anysuitable technique to synthesize the parity data. In someimplementations, the aggregate object 170 is associated with parity datathat occupies a set of parity blocks in the parity storage entities 120.In such implementations, the ingest entity 130 writes the parity datafor the small object 150 into one or more of the parity blocksassociated with the aggregate object 170. In some implementations, theingest entity 130 updates a processed data end offset indicator (notshown) to indicate that the parity data for the aggregate object 170includes valid data up to and including the small object 150. In otherwords, in some implementations, after storing the parity data for thesmall object 150, the ingest entity 130 updates the processed data endoffset indicator to indicate that the parity data is usable to recoverthe small object 150.

In some implementations, the storage system 100 sends (e.g., transmits)a write confirmation 178 (e.g., a message) to the client device 20. Insome implementations, the write confirmation 178 acknowledges therequest to store the small object 150. In some implementations, thewrite confirmation 178 indicates that the small object 150 has beenstored in the storage system 100. Additionally or alternatively, thewrite confirmation 178 indicates that parity data for the small object150 has been synthesized and stored in the storage system 100. In someexamples, the write confirmation 178 indicates that the small object 150is fault-tolerant.

In various implementations, the client devices 20 include any suitablecomputing device, such as a computer, a laptop computer, a tabletdevice, a netbook, an internet kiosk, a personal digital assistant, amobile phone, a smartphone, a wearable, a gaming device, a computerserver, etc. In some implementations, each client device 20 (e.g., amobile computing device 20 a, a laptop computer 20 b, a desktop computer20 c, a television 20 d, etc.) includes one or more processors, one ormore types of memory, a display and/or other user interface componentssuch as a keyboard, a touch screen display, a mouse, a track-pad, adigital camera and/or any number of supplemental devices to addfunctionality. In some implementations, a client device 20 includes asuitable combination of hardware, software and firmware configured toprovide at least some of protocol processing, modulation, demodulation,data buffering, power control, routing, switching, clock recovery,amplification, decoding, and error control.

FIG. 2 is a block diagram of the storage system 100 in accordance withsome implementations. As exemplified, in various implementations, thedata storage entity 110 includes various data blocks 112. In someimplementations, a data block 112 refers to the smallest addressableblock of memory (e.g., the smallest allocation unit of data) in the datastorage entity 110. A data block 112 is associated with a data blocksize 114. In some implementations, the data block size 114 is a constant(e.g., a runtime constant). In some examples, the data block size 114 isadjustable by an operator of the storage system 100. In some scenarios,the data block size 114 is several megabytes (e.g., 2 MB). A collectionof data blocks 112 at a particular data storage entity 110 is referredto as a data stripe (e.g., data stripe 116-1, data stripe 116-2 . . .data stripe 116-N).

In various implementations, the parity storage entity 120 includesvarious parity blocks 122. In some implementations, a parity block 122refers to the smallest addressable block of memory (e.g., the smallestallocation unit of data) in the parity storage entity 120. A parityblock 122 is associated with a parity block size 124. In someimplementations, the parity block size 124 is a constant (e.g., aruntime constant). In some examples, the parity block size 124 isadjustable by an operator of the storage system 100. In some scenarios,the parity block size 124 is several megabytes (e.g., 2 MB). Asexemplified in FIG. 2, in various implementations, the parity block size124 is equal to the data block size 114. However, in someimplementations, the parity block size 124 is different from the datablock size 114. A collection of parity blocks 122 at a particular paritystorage entity 120 is referred to as a parity stripe (e.g., paritystripe 126-1, parity stripe 126-2 . . . parity stripe 126-M).

The aggregate object 170 is associated with an aggregate object size172. In various implementations, the aggregate object size 172 is atleast an order of magnitude larger than the data block size 114 and/orthe parity block size 124. For example, in some implementations, if thedata block size 114 and the parity block size 124 is several megabytes,then the aggregate object size 172 is several gigabytes (e.g., more than1 GB). As illustrated in FIG. 2, in various implementations, theaggregate object 170 is distributed across multiple data storageentities 110. Similarly, in various implementations, the parity data forthe aggregate object 170 is distributed across multiple parity storageentities 120. In such implementations, each parity storage entity 120stores different parity data for the aggregate object 170 to provide anadditional level of resiliency.

In various implementations, the ingest entity 130 includes a writingmodule 132, a recovery module 134, a deletion module 136, a compactionmodule 137, and a database 138. In various implementations, the writingmodule 132, the recovery module 134, the deletion module 136, and/or thecompaction module 137 are implemented in hardware (e.g., as one or moreapplication specific integrated circuits (ASICs)) and/or in software(e.g., as one or more sets of computer readable instructions that areexecuted by one or more central processing units). In variousimplementations, the database 138 stores a processed data end offsetindicator 140. In some implementations, the processed data end offsetindicator 140 is an indicator that indicates what the parity blocks 122associated with the aggregate object 170 represent. Additionally oralternatively, the processed data end offset indicator 140 indicates theamount of valid data in a partially utilized data block 112. In someimplementations, the processed data end offset indicator 140 includes avalue that indicates whether the parity data associated with theaggregate object 170 includes valid data for the small object 150. Inother words, in some implementations, the processed data end offsetindicator 140 indicates whether the ingest entity 130 can recover thesmall object 150 based on the parity data. In various implementations,the database 138 stores object names 142 for the objects that are storedin the data storage entities 110.

In various implementations, the writing module 132 writes the smallobject 150 into the aggregate object 170. In some implementations, thewriting module 132 receives a write request 148 to store the smallobject 150. Upon receiving the write request 148, the writing module 132writes the small object 150 into the aggregate object 170. In someimplementations, the write request 148 includes the small object 150. Insuch implementations, the writing module 132 retrieves the small object150 from the write request 148. In some implementations, the writerequest 148 includes an object identifier (ID) (e.g., a URI) thatidentifies the small object 150, or a link (e.g., a URL) for the smallobject 150. In such implementations, the writing module 132 utilizes theobject ID or the link to obtain the small object 150.

In various implementations, the writing module 132 writes the smallobject 150 into the aggregate object 170 by writing the object data forthe small object 150 into the data blocks 112 associated with theaggregate object 170. In some implementations, the writing module 132synthesizes parity data for the small object 150. The writing module 132utilizes any suitable technique for synthesizing the parity data for thesmall object 150. In some implementations, the writing module 132 writesthe parity data for the small object 150 into the parity blocks 122associated with the aggregate object 170.

In various implementations, the writing module 132 updates the processeddata end offset indicator 140 to indicate that the parity data for theaggregate object 170 includes valid data for the small object 150. Invarious implementations, the writing module 132 determines a smallobject size 152 for the small object 150. In some implementations, thewriting module 132 determines the small object size 152 based onmetadata associated with the small object 150. In some implementations,the writing module 132 updates the processed data end offset indicator140 by incrementing a value of the processed data end offset indicator140 by the small object size 152. Additionally or alternatively, thewriting module 132 inserts (e.g., writes) an object name 142 for thesmall object 150 into the database 138, for example, in order to keeptrack of the objects that have been written into the aggregate object170.

In some implementations, the writing module 132 sends a writeconfirmation 178 upon writing the small object 150 into the aggregateobject 170. The write confirmation 178 indicates that the small object150 has been written into the aggregate object 170. Additionally oralternatively, the write confirmation 178 indicates that the smallobject 150 is fault-tolerant. In other words, in some implementations,the write confirmation 178 indicates that the small object 150 isrecoverable in the event of a data loss at one of the data storageentities 110 that stores a portion of the small object 150.

In various implementations, the recovery module 134 recovers the smallobject 150 in the event of a data loss at one of the data storageentities 110 that stored a portion of the small object 150. In someimplementations, the recovery module 134 detects that a portion of theobject data for the small object 150 has been lost, for example, due toa loss of data event at one of the data storage entities 110. Exampleevents that result in a loss of data include power outages, diskfailures, data corruption, etc. Upon detecting that a portion of thesmall object 150 has been lost, the recovery module 134 determineswhether the small object 150 is recoverable based on the parity dataassociated with the aggregate object 170. For example, in someimplementations, the recovery module 134 determines whether theprocessed data end offset indicator 140 indicates that the parity dataassociated with the aggregate object 170 includes valid data for thesmall object 150.

In some implementations, the recovery module 134 utilizes the paritydata to recover the small object 150, if a value of the processed dataend offset indicator 140 is equal to the sum of object sizes for variousobjects (e.g., all objects) that have been written into the aggregateobject 170. In such implementations, the recovery module 134 accessesthe database 138 to identify objects (e.g., all objects) that have beenwritten into the aggregate object 170. Upon identifying the objects, therecovery module 134 determines the object size for each object that hasbeen written into the aggregate object 170. Thereafter, the recoverymodule 134 computes a sum by adding the object sizes (e.g., all objectsizes). If the value of the processed data end offset indicator 140 isequal to the sum, then the recovery module 134 determines that theparity data associated with the aggregate object 170 includes valid datafor the small object 150. Therefore, the recovery module 134 is able torecover the small object 150 based on the parity data. The recoverymodule 134 utilizes any suitable technique to recover the small object150 from the parity data. In some implementations, the aggregate objectsize 172 represents the sum of object sizes for all objects that havebeen written into the aggregate object 170. In such implementations, therecovery module 134 uses the parity data to recover the small object150, if the value of the processed data end offset indicator 140 isequal to the aggregate object size 172.

In various implementations, the deletion module 136 deletes an objectfrom the aggregate object 170. In some implementations, the deletionmodule 136 deletes an object in response to receiving a delete request144 to delete the object. For example, sometime after writing the smallobject 150 into the aggregate object 170, the ingest entity 130 mayreceive the delete request 144 to delete the small object 150. In someimplementations, the delete request 144 includes an object name 142 foran object that is to be deleted. In some implementations, the deletionmodule 136 removes the object name 142 specified in the delete request144 from the database 138. In various implementations, when the objectname 142 for an object is removed from the database 138, the object isno longer accessible by a device external to the storage system 100. Inaddition to deleting the object name 142 from the database 138, invarious implementations, the deletion module 136 marks the data blocks112 associated with the corresponding object as invalid. In someimplementations, the deletion module 136 sends a delete confirmation 146that indicates that the object has been deleted.

In various implementations, the compaction module 137 compacts theaggregate object 170. In some implementations, the compaction module 137determines to compact the aggregate object 170 when the aggregate object170 appears sparse. For example, in some implementations, the compactionmodule 137 compacts the aggregate object 170 when the number orpercentage of data blocks 112 that are marked as invalid exceeds athreshold (e.g., 25-50%). In some implementations, the compaction module137 compacts the aggregate object 170 by instantiating a new aggregateobject, and migrating the valid data blocks from the aggregate object170 to the new aggregate object. The valid data blocks refer to datablocks 112 that store object data for an object that is listed in thedatabase 138. By contrast, invalid data blocks refer to the data blocks112 that store data for an object that is not listed in the database 138because its corresponding object name 142 has been removed from thedatabase 138.

FIG. 3A is a flowchart representation of a method 300 of writing smallobjects in a storage system. In various implementations, the method 300is implemented as a set of computer readable instructions that areexecuted at the storage system. For example, in various implementations,the method 300 is performed by the writing module 132 shown in FIG. 2.Briefly, the method 300 includes writing a small object into anaggregate object (at block 310), updating parity data of the aggregateobject based on the small object (at block 320), and updating aprocessed data end offset indicator to indicate that the parity data forthe aggregate object includes valid data for the small object (at block330).

As represented by block 310, in various implementations, the method 300includes writing a small object into an aggregate object that isdistributed across multiple data storage entities. In variousimplementations, the small object refers to an object that is at leastan order of magnitude smaller than the aggregate object. In someimplementations, a small object size is within the same order ofmagnitude of a block unit (e.g., a data block) addressable within eachof the storage entities. By contrast, the aggregate object is at leastan order of magnitude larger than a data block. In variousimplementations, writing the small object includes writing object datathat is associated with the small object into data blocks that have beenassigned to the aggregate object. In some implementations, the method300 utilizes techniques associated with distributed erasure coding towrite the small object into the aggregate object (e.g., as described inrelation to FIG. 1).

As represented by block 320, in various implementations, the method 300includes updating the parity data associated with the aggregate objectbased on the small object. In various implementations, the method 300includes synthesizing parity data for the small object. The method 300utilizes any suitable technique for synthesizing the parity data for thesmall object. Upon synthesizing the parity data for the small object, invarious implementations, the method 300 includes writing the parity datafor the small object into parity blocks that are associated with theaggregate object. More generally, the method 300 includes updating,based on the small object, parity data associated with the aggregateobject in response to writing the small object into the aggregateobject. In various implementations, the parity data is stored at one ormore parity storage entities.

As represented by block 330, in various implementations, the method 300includes updating a processed data end offset indicator to indicate thatthe parity data for the aggregate object includes valid data up to andincluding the small object. In some implementations, the method 300updates the processed data end offset indicator by incrementing a valueof the processed data end offset indicator. Moreover, in someimplementations, incrementing the value of the processed data end offsetindicator includes increasing its value by the size of the small object.

FIG. 3B is a flowchart representation of a method 300 a of writing smallobjects in a storage system. In various implementations, the method 300a is implemented as a set of computer readable instructions that areexecuted at the storage system. For example, in various implementations,the method 300 a is performed by the writing module 132 shown in FIG. 2.Briefly, the method 300 a includes writing a small object into anaggregate object (at block 310), updating parity data of the aggregateobject based on the small object (at block 320), updating a processeddata end offset indicator (at block 330), and transmitting a messageindicating that the small object has been written into the storagesystem (at block 340).

As represented by block 310, in various implementations, the method 300a includes receiving a write request (at block 312). In variousimplementations, the method 300 a includes receiving the write requestfrom a client device (e.g., the client device 20 shown in FIG. 1). Insome implementations, the write request includes the small object thatis to be stored in the storage system. In such implementations, themethod 300 a includes retrieving the small object from the request. Insome implementations, the write request specifies an object ID for thesmall object, or a link for the small object. In such implementations,the method 300 a includes utilizing the object ID or the link to fetchthe small object. As represented by block 314, in variousimplementations, the method 300 a includes writing object dataassociated with the small object into data blocks associated with theaggregate object.

As represented by block 320, in various implementations, the method 300a includes updating parity data associated with the aggregate objectbased on the small object. In various implementations, the method 300 aincludes synthesizing the parity data for the small object (at block322). The method 300 a utilizes any suitable technique for synthesizingthe parity data for the small object. As represented by block 324, invarious implementations, the method 300 a includes writing the paritydata for the small object into parity blocks. The parity blockscorrespond with data blocks that store object data for the small object.

As represented by block 330, in various implementations, the method 300a includes updating a processed data end offset indicator. In variousimplementations, the method 300 a includes determining a size of thesmall object (at block 332). In various implementations, the method 300a includes determining the size of the small object based on metadataassociated with the small object. In various implementations, the method300 a includes updating the processed data end offset indicator byincrementing its value with the size of the small object (at block 334).The updated processed data end offset indicator indicates that theparity data for the aggregate object includes valid data for the smallobject. In other words, the updated processed data end offset indicatorindicates that the parity data for the aggregate object is usable torecover the small object in the event of a data loss at the data blocksthat store object data for the small object. In some implementations,upon being updated, the value of the processed data end offset indicatoris equal to the size of the aggregate object.

As represented by block 340, in some implementations, the method 300 aincludes transmitting a message (e.g., the write confirmation 178 shownin FIGS. 1 and 2). In some implementations, the message represents awrite confirmation that indicates that the small object has been writteninto the storage system. Additionally or alternatively, the messageindicates that the small object is fault tolerant. In other words, themessage indicates that the small object is recoverable in the event of adata loss. In various implementations, the method 300 a includestransmitting the message to the same client device from which the method300 a received the write request at block 312.

In some implementations, the method 300 a includes determining whether asize of the small object is greater than a threshold size. In suchimplementations, if the size of the small object is greater than thethreshold size, the method 300 a includes updating the parity data inresponse to determining that the size of the small object is greaterthan the threshold size (as represented by blocks 320 and 330,respectively). However, in some implementations, if the size of thesmall object is less than the threshold size, the method 300 a includeswaiting for a predetermined amount of time to update the parity data andthe processed data end offset indicator. In some implementations, themethod 300 a includes updating the parity data and the processed dataend offset indicator before the predetermined amount of time expires, ifan additional small object is to be written into the aggregate objectand the total object size is greater than the threshold size. In theseimplementations, the total object size represents a sum of both smallobject sizes. In some implementations, the method 300 a includesupdating the parity data while the small object is being written intothe aggregate object, and updating the parity data after the smallobject has been written into the aggregate object.

FIG. 4A is a flowchart representation of a method 400 of recoveringsmall objects upon detecting a loss of data at a storage entity inaccordance with some implementations. In various implementations, themethod 400 is implemented as a set of computer readable instructionsthat are executable at the storage system. For example, in variousimplementations, the method 400 is performed by the recovery module 134shown in FIG. 2. Briefly, the method 400 includes detecting loss of dataat a data storage entity that stored a small object (at block 410),determining whether a processed data end offset indicator indicates thatthe parity data associated with an aggregate object includes valid datafor the small object (at block 420), and recovering the small objectbased on the parity data (at block 440).

As represented by block 410, in various implementations, the method 400includes detecting a loss of data at a data storage entity that stored asmall object within an aggregate object. In some implementations, theloss of data results in at least a portion of the object data for thesmall object being lost. The loss of data occurs due to a variety ofreasons (e.g., loss of power, disk failure, server crashing, etc.).

As represented by block 420, in various implementations, the method 400includes determining whether a processed data end offset indicatorindicates that the parity data associated with the aggregate objectincludes valid data for the small object. In other words, in variousimplementations, the method 400 includes determining whether the paritydata for the aggregate object includes parity data for the small object.Put another way, in various implementations, the method 400 includesdetermining whether the parity data is usable for properly recoveringthe small object. In some implementations, the method 400 performs theoperations exemplified in FIG. 4B at block 420. If the processed dataend offset indicator indicates that the parity data for the aggregateobject includes valid data for the small object, then the method 400proceeds to 440, otherwise the method 400 ends.

As represented by block 440, in various implementations, the method 400includes recovering the small object based on the parity data associatedwith the aggregate object and/or the remaining object data associatedwith the aggregate object. The method 400 utilizes any suitabletechnique for recovering the small object based on the parity data. Invarious implementations, recovering the small object includesrebuilding, reconstructing, restoring, and/or repairing the small objectfrom the parity data.

FIG. 4B is a flowchart representation of a method 420 of determiningwhether the parity data associated with an aggregate object includesvalid data for a small object in accordance with some implementations.In various implementations, the method 420 is performed at block 420shown in FIG. 4A. Briefly, the method 420 includes identifying theobjects in the aggregate object (at block 422), determining a sum thatrepresents the total size of the objects (at blocks 424 and 426),comparing the processed data end offset indicator with the sum (at block428), and determining that the parity data includes valid data for thesmall object based on the comparison (at block 430).

As represented by block 422, in some implementations, the method 420includes identifying a set of objects that have been written into theaggregate object. In various implementations, the method 420 includesaccessing a database (e.g., the database 138 shown in FIG. 2) toidentify the set of objects that have been written into the aggregateobject. In some implementations, the set of objects includes the objectthat is being recovered and the objects that were written into theaggregate object prior to the object that is being recovered. In otherwords, in some implementations, the set of objects does not includeobjects that were written into the aggregate object after the objectthat is being recovered was written into the aggregate object.

In various implementations, the method 420 includes identifying a sizefor each object that is in the set (at block 424). In variousimplementations, the method 420 includes retrieving the size for eachobject from the database. As represented by block 426, in variousimplementations, the method 420 includes computing a sum by adding thesizes for all the objects in the set.

As represented by block 428, in various implementations, the method 420includes determining whether the processed data end offset indicator isequal to the sum. In some implementations, if the processed data endoffset indicator is not equal to the sum, then the method 420 ends.However, in some implementations, if the processed data end offsetindicator is equal to the sum, then the method 420 proceeds to block430. As represented by block 430, in various implementations, the method420 includes determining that the parity data for the aggregate objectincludes valid data for the small object. Hence, the parity data for theaggregate object is usable for recovering the small object (e.g., asdescribed in relation to block 440 in FIG. 4A).

FIG. 5A is a flowchart representation of a method 500 of deleting smallobjects from the storage system in accordance with some implementations.In various implementations, the method 500 is implemented as a set ofcomputer readable instructions that are executable at the storagesystem. For example, in various implementations, the method 500 isperformed by the deletion module 136 shown in FIG. 2. Briefly, themethod 500 includes determining to delete a small object from anaggregate object (at block 510), removing the name of the small objectfrom a database (at block 520), and marking the data blocks that storedthe object data for the small object as invalid (at block 530).

As represented by block 510, in various implementations, the method 500includes determining to delete a small object from an aggregate objectthat stores the small object. In various implementations, the method 500includes receiving a delete request from a client device to delete aparticular small object. In some implementations, the delete requestspecifies the name of the small object that is to be deleted from thestorage system. In some implementations, the method 500 determines to adelete a small object based on an age of the small object. In someimplementations, the method 500 determines to delete a small objectbased on a usage of the small object. For example, the method 500determines to delete a small object that has not been requested by aclient device for a threshold amount of time. In some implementations,the method 500 determines to delete a small object based on a size ofthe aggregate object (e.g., if the size of the aggregate object exceedsa threshold size).

As represented by block 520, in various implementations, the method 500includes removing the name of the small object from a database (e.g.,the database 138 shown in FIG. 2). In some implementations, the databasestores the names of all objects that have been written into theaggregate object. In various implementations, the method 500 includesmarking the data blocks that stored the small object as invalid, asrepresented by block 530. Since the name of the small object has beenremoved from the database and the data blocks corresponding with thesmall object have been marked as invalid, the small object is no longeraccessible by a client device. As such, in some implementations, if aclient device requests the small object, the storage system returnsnull.

FIG. 5B is a flowchart representation of a method 550 of compacting anaggregate object in accordance with some implementations. In variousimplementations, the method 550 is implemented as a set of computerreadable instructions that are executable at the storage system. Forexample, in various implementations, the method 550 is performed by thecompaction module 137 shown in FIG. 2. Briefly, the method 550 includesdetermining a percentage or a number of data blocks that have beenmarked as invalid (at block 560), determining whether the percentage ornumber is higher than a threshold (at block 570), and compacting theaggregate object based on the determination (at block 580).

As represented by block 560, in some implementations, the method 550includes determining a percentage of data blocks in the aggregate objectthat have been marked as invalid. In various implementations, the method550 includes counting the number of invalid data blocks, and dividingthe number of invalid data blocks by the total number of data blocks todetermine the percentage. In various implementations, the method 550includes determining whether the percentage is higher than a threshold,as represented by block 570. In some implementations, the threshold is aconstant that is configurable by an administrator of the storage system(e.g., via an administrator console). In some examples, the thresholdranges from 25% to 50%. If the percentage is lower than the threshold,then the method 550 includes waiting until the percentage is higher thanthe threshold. However, if the percentage is higher than the threshold,then the method 550 proceeds to block 580.

In various implementations, the method 550 includes compacting theaggregate object, as represented by block 580. In some implementations,compacting the aggregate object includes instantiating a new aggregateobject (as represented by block 582), and migrating the valid datablocks to the new aggregate object (as represented by block 584). Insome implementations, instantiating a new aggregate object refers tocreating a new aggregate object. In some implementations, migrating thevalid data blocks refers to copying the data stored in the valid datablocks from the old aggregate object to the new aggregate object. Invarious implementations, when the valid data blocks have been migratedto the new aggregated object, the method 550 includes purging the oldaggregate object.

More generally, in some implementations, the method 550 includesdetermining a level of sparsity for the aggregate object. In someimplementations, the percentage of invalid data blocks indicates thelevel of sparsity. In some implementations, if the level of sparsityexceeds a threshold, then the method 550 includes compacting theaggregate object (as represented by block 580). However, in someimplementations, if the level of sparsity is below the threshold, themethod 550 includes delaying the compaction until the level of sparsityexceeds the threshold.

FIG. 6 is a diagram that illustrates small objects being written into astorage system 600 in accordance with some implementations. In variousimplementations, the storage system 600 is similar to the storage system100 exemplified in FIGS. 1 and 2. For example, in variousimplementations, the storage system 600 includes a first data storageentity 610-1, a second data storage entity 610-2, and a parity storageentity 620. In some implementations, the data storage entities 610include data blocks 612 of a particular data block size 614. In theexample of FIG. 6, the data block size 614 is 2 MB. Similarly, in someimplementations, the parity storage entity 620 includes parity blocks622 of a particular parity block size 624. In the example of FIG. 6, theparity block size 624 is 2 MB. In the example of FIG. 6, the data blocksize 614 and the parity block size 624 are equal. However, in someimplementations, the data block size 614 and the parity block size 624are different.

As illustrated in FIG. 6, at time T₁, the storage system 600 determinesto write object A. For example, in some implementations, the storagesystem 600 receives a request from a client device to store object A. Inthe example of FIG. 6, object A has a size of 1 MB. Object A qualifiesas the small object 150 shown in FIGS. 1 and 2, for example, because thesize of object A is less than the data block size 614. In someimplementations, the storage system 600 writes object A into the firstdata block 612-1. Since the size of object A is half the data block size614, object A only occupies half of the first data block 612-1.

In various implementations, the storage system 600 synthesizes paritydata for object A, and writes the parity data into the first parityblock 622-1. As illustrated in FIG. 6, in various implementations, thesize of object A is 1 MB, and the parity data for object A occupies 1 MBof storage space available in the first parity block 622-1. In variousimplementations, upon storing the parity data for object A, the storagesystem 600 updates a value of a processed data end offset indicator 640.In some implementations, the storage system 600 increments the value ofthe processed data end offset indicator 640 by the size of object A.Hence, in the example of FIG. 6, the storage system 600 sets the valueof the processed data end offset indicator 600 to 1 MB.

At time T₂, the storage system 600 determines to write object B. In theexample of FIG. 6, object B has a size of 3 MB. Object B qualifies asthe small object shown in FIGS. 1 and 2, for example, because the sizeof object B is of the same order of magnitude as the data block size614. In some implementations, the storage system 600 writes 1 MB ofobject B into the first data block 612-1, and the remaining 2 MB ofobject B into the second data block 612-2. In various implementations,the storage system 600 synthesizes parity data for object B, and writesthe parity data for object B in the first parity block 622-1. At timeT₂, the first parity block 622-1 includes parity data for object A andobject B. The storage system 600 increments the processed data endoffset indicator 640 by the size of object B. Hence, after writing theparity data for object B, the processed data end offset indicator 640 isset to 4 MB.

At time T₃, the storage system 600 determines to write object C. In theexample of FIG. 6, object C has a size of 2 MB. In some implementations,the storage system 600 writes object C into the third data block 612-3.Moreover, in various implementations, the storage system 600 synthesizesthe parity data for object C, and writes the parity data into the secondparity block 622-2. Furthermore, in some implementations, the storagesystem 600 increments the processed data end offset indicator 640 by thesize of object C. Hence, after writing the parity data for object C, theprocessed data end offset indicator 640 is set to 6 MB. As indicated bythe processed data end offset indicator 640, at time T₃, the storagesystem 600 stores 6 MB of object data but only 4 MB of parity data.

At time T₄, the storage system 600 determines to write object D. In theexample of FIG. 6, object D has a size of 2 MB. In some implementations,the storage system 600 writes object D into the fourth data block 612-4.In various implementations, the storage system 600 synthesizes paritydata for object D, and writes the parity data into the second parityblock 622-2. Furthermore, the storage system 600 increments theprocessed data end offset indicator 640 by the size of object D. Hence,after writing the parity data for object D, the processed data endoffset indicator 640 is set to 8 MB. As exemplified, after writing theparity data for object D, the storage system 600 stores 8 MB of objectdata and 4 MB of parity data.

In the example of FIG. 6, the amount of parity data remains constant at4 MB at times T₃ and T₄. In other words, the amount of parity dataremains constant at 4 MB immediately before and immediately after objectD is written into the storage system 600. Hence, in someimplementations, without the processed data end offset indicator 640,the storage system 600 is unable to determine whether the parity datastored in the second parity block 622-2 includes valid data for objectD. However, in various implementations, the storage system 640determines whether the second parity block 622-2 includes valid data forobject D based on the value of the processed data end offset indicator640. In the example of FIG. 6, if the value of the processed data endoffset indicator 640 is 6 MB, then the storage system 600 determinesthat the second parity block 622-2 includes valid data for object C butnot object D. However, if the value of the processed data end offsetindicator 640 is 8 MB, then the storage system 600 determines that thesecond parity block 622-2 includes valid data for object C and object D.Hence, in the example of FIG. 6, if the value of the processed data endoffset indicator 640 is 8 MB, the storage system 600 is able to recoverobject D upon detecting a loss of data at the fourth data block 612-4.

FIG. 7 is a diagram that illustrates small objects being written into astorage system 700 in accordance with some implementations. In variousimplementations, the storage system 700 is similar to the storage system100 exemplified in FIGS. 1 and 2. For example, in variousimplementations, the storage system 700 includes a first data storageentity 710-1, a second data storage entity 710-2, and a parity storageentity 720. In some implementations, the data storage entities 710include data blocks 712 of a particular data block size 714. In theexample of FIG. 7, the data block size 714 is 2 MB. Similarly, invarious implementations, the parity storage entity 720 includes parityblocks 722 of a particular parity block size 724. In the example of FIG.7, the parity block size 724 is 2 MB. In the example of FIG. 7, the datablock size 714 and the parity block size 724 are equal. However, in someimplementations, the data block size 714 and the parity block size 724are different.

At time T₁₀, the storage system 700 determines to write object w. Forexample, in some implementations, the storage system 700 receives arequest from a client device to store object w. In the example of FIG.7, object w has a size of 2 MB. Object w qualifies as the small object150 shown in FIGS. 1 and 2, for example, because the size of object w isof the same order of magnitude as the data block size 714. In variousimplementations, the storage system 700 writes object w into the firstdata block 712-1. Since the size of object w is equal to the data blocksize 714, object w occupies the entire first data block 712-1.

In various implementations, the storage system 700 synthesizes paritydata for object w, and writes the parity data into the first parityblock 722-1. As illustrated in FIG. 7, the size of object w is 2 MB, andthe parity data for object w occupies the entire 2 MB of storage spaceavailable in the first parity block 722-1. Upon storing the parity datafor object w, the storage system 700 updates a value of a processed dataend offset indicator 740. In some implementations, the storage system700 increments the value of the processed data end offset indicator 740by the size of object w. Hence, in the example of FIG. 7, the storagesystem 700 increases the value of the processed data end offsetindicator 700 by 2 MB.

At time T₁₁, the storage system 700 determines to write object x. Forexample, in some implementations, the storage system 700 receives arequest from a client device to store object x. In the example of FIG.7, object x has a size of 100 kB. Object x qualifies as the small object150 shown in FIGS. 1 and 2, for example, because the size of object x isless than the data block size 714. In various implementations, thestorage system 700 writes object x into the second data block 712-2since the first data block 712-1 is full. Since the size of object x ismuch smaller than the data block size 714, object x occupies only aportion of the second data block 712-2.

In various implementations, the storage system 700 synthesizes paritydata for object x, and writes the parity data into the first parityblock 722-1. As illustrated in FIG. 7, although the collective size ofobjects w and x is 2.1 MB, in some implementations, the parity data forobjects w and x only occupies 2 MB of storage space. Upon storing theparity data for object x, the storage system 700 updates a value of aprocessed data end offset indicator 740. In some implementations, thestorage system 700 increments the value of the processed data end offsetindicator 740 by the size of object x. Hence, in the example of FIG. 7,the storage system 700 increases the value of the processed data endoffset indicator 700 by 100 kB.

At time T₁₂, the storage system 700 determines to write object y. In theexample of FIG. 7, object y has a size of 30 kB. Similar to object x,object y also qualifies as the small object 150 shown in FIGS. 1 and 2,for example, because the size of object y is less than the data blocksize 714. The storage system 700 writes object y into the second datablock 712-2. The storage system 700 synthesizes parity data for objecty, and writes the parity data for object y in the first parity block722-1. Hence, at time T₁₂, the first parity block 722-1 includes paritydata for objects w, x and y. The storage system 700 increments theprocessed data end offset indicator 740 by the size of object y. Hence,in this example, after writing the parity data for object y, theprocessed data end offset indicator 740 is set to 2.13 MB.

At time T₁₃, the storage system 700 determines to write object z. In theexample of FIG. 7, object z has a size of 120 kB. The storage system 700writes object z into the second data block 712-2. Moreover, the storagesystem 700 synthesizes the parity data for object z, and writes theparity data into the first parity block 722-1. Furthermore, the storagesystem 700 increments the processed data end offset indicator 740 by thesize of object z. Hence, after writing the parity data for object z, theprocessed data end offset indicator 740 is set to 2.25 MB. It is worthnoting that, as indicated by the processed data end offset indicator740, the storage system 700 stores 2.25 MB of object data but only 2 MBof parity data.

In the example of FIG. 7, the amount of parity data remains constant at2 MB at times T₁₁ and T₁₂. In other words, the amount of parity dataremains constant at 2 MB immediately before and immediately after objecty is written into the storage system 700. Hence, in variousimplementations, without the processed data end offset indicator 740,the storage system 700 is unable to determine whether the parity datastored in first parity block 722-1 includes valid data for object y.However, in various implementations, the storage system 740 determineswhether the first parity block 722-1 includes valid data for object ybased on the value of the processed data end offset indicator 740. Inthe example of FIG. 7, if the value of the processed data end offsetindicator 740 is 2.1 MB, then the storage system 700 determines that thefirst parity block 722-1 includes valid data for objects w and x, butnot object y. However, if the value of the processed data end offsetindicator 740 is 2.13 MB, then the storage system 700 determines thatthe first parity block 722-1 includes valid data for objects w, x and y.Hence, in this example, if the value of the processed data end offsetindicator 740 is 2.13 MB, the storage system 700 is able to recoverobject y upon detecting a loss of data at the second data block 712-2.

Similarly, the amount of parity data remains constant at 2 MB at timesT₁₂ and T₁₃. In other words, the amount of parity data remains constantat 2 MB immediately before and immediately after object z is writteninto the storage system 700. Hence, without the processed data endoffset indicator 740, in some implementations, the storage system 700 isunable to determine whether the parity data stored in first parity block722-1 includes valid data for object z. However, in variousimplementations, the storage system 740 determines whether the firstparity block 722-1 includes valid data for object z based on the valueof the processed data end offset indicator 740. In the example of FIG.7, if the value of the processed data end offset indicator 740 is 2.13MB, then the storage system 700 determines that the first parity block722-1 includes valid data for objects w, x and y, but not object z.However, if the value of the processed data end offset indicator 740 is2.25 MB, then the storage system 700 determines that the first parityblock 722-1 includes valid data for objects w, x, y and z. Hence, inthis example, if the value of the processed data end offset indicator740 is 2.25 MB, the storage system 700 is able to recover object z upondetecting a loss of data at the second data block 712-2.

FIG. 8 is a block diagram of a server system 800 enabled with one ormore components of a storage system (e.g., the storage system 100 shownin FIGS. 1 and 2) according to some implementations. While certainspecific features are illustrated, those of ordinary skill in the artwill appreciate from the present disclosure that various other featureshave not been illustrated for the sake of brevity, and so as not toobscure more pertinent aspects of the implementations disclosed herein.To that end, as a non-limiting example, in some implementations theserver system 800 includes one or more processing units (CPUs) 802, anetwork interface 803, a memory 810, a programming interface 808, andone or more communication buses 804 for interconnecting these andvarious other components.

In some implementations, the network interface 803 is provided to, amongother uses, establish and maintain a metadata tunnel between a cloudhosted network management system and at least one private networkincluding one or more compliant devices. In some implementations, thecommunication buses 804 include circuitry that interconnects andcontrols communications between system components. The memory 810includes high-speed random access memory, such as DRAM, SRAM, DDR RAM orother random access solid state memory devices; and may includenon-volatile memory, such as one or more magnetic disk storage devices,optical disk storage devices, flash memory devices, or othernon-volatile solid state storage devices. The memory 810 optionallyincludes one or more storage devices remotely located from the CPU(s)802. The memory 810 comprises a non-transitory computer readable storagemedium.

In some implementations, the memory 810 or the non-transitory computerreadable storage medium of the memory 810 stores the following programs,modules and data structures, or a subset thereof including an optionaloperating system 830, a writing module 832, a recovery module 834, adeletion module 836, a compaction module 837, and a database 838. Invarious implementations, the writing module 832, the recovery module834, the deletion module 836, the compaction module 837, and thedatabase 838 are similar to the writing module 132, the recovery module134, the deletion module 136, the compaction module 137 and the database138, respectively shown in FIG. 2. In various implementations, thedatabase 838 stores a processed data end offset indicator 840 (e.g., theprocessed data end offset indicator 140 shown in FIG. 1), and objectnames 842 (e.g., the object names 142 shown in FIG. 1).

The operating system 830 includes procedures for handling various basicsystem services and for performing hardware dependent tasks.

In some implementations, the writing module 832 is configured to write asmall object into an aggregate object. For example, as illustrated inFIGS. 1 and 2, the writing module 832 writes the small object 150 intothe aggregate object 170. In various implementations, the writing module832 also synthesizes parity data for the small object, and writes theparity data into parity blocks associated with the aggregate object.Upon writing the parity data for the small object, the writing module832 updates the processed data end offset indicator 840. For example, invarious implementations, the writing module 832 increments the processeddata end offset indicator 840 by a size of the small object. In someimplementations, the writing module 832 performs the method 300illustrated in FIG. 3A, and/or the method 300 a illustrated in FIG. 3B.To that end, in various implementations, the writing module 832 includesinstructions and/or logic 832 a, and heuristics and metadata 832 b.

In various implementations, the recovery module 834 is configured torecover small objects (e.g., the small object 150 shown in FIGS. 1 and2). In some implementations, the recovery module 834 detects that atleast a portion of the object data associated with the small object hasbeen lost. In some implementations, the recovery module 834 recovers thesmall object based on the remaining object data and/or the parity dataassociated with the small object. In various implementations, therecovery module 834 recovers the small object based on the parity data,if the processed data end offset indicator 840 indicates that the paritydata for the aggregate object includes valid data for the small object.For example, in some implementations, the recovery module 834 performsthe method 400 illustrated in FIG. 4A, and/or the method 420 illustratedin FIG. 4B. To that end, in various implementations, the recovery module834 includes instructions and/or logic 834 a, and heuristics andmetadata 834 b.

In various implementations, the deletion module 836 is configured todelete an object (e.g., a small object) from the storage system (e.g.,the aggregate object). In some implementations, the deletion module 836removes the name of the object from the database 838, and marks the datablocks associated with the object as invalid. The deletion module 836uses any suitable techniques(s) to mark the data blocks as invalid. Insome implementations, the deletion module 836 performs the method 500illustrated in FIG. 5A. To that end, in various implementations, thedeletion module 836 includes instructions and/or logic 836 a, andheuristics and metadata 836 b.

In various implementations, the compaction module 837 is configured toperform a compaction of the aggregate object. In some implementations,the compaction module 837 performs the compaction when thenumber/percentage of invalid data blocks exceeds a threshold. Moregenerally, in some implementations, the compaction module 837 compactsthe aggregate object when the aggregate object appears sparse. Forexample, in some implementations, the compaction module 837 compacts theaggregate object when a level of sparsity of the aggregate object isgreater than a threshold. In some implementations, the compaction module837 performs the compaction of the aggregate object by instantiating anew aggregate object, and migrating the valid data blocks from theaggregate object to the new aggregate object. In variousimplementations, the compaction module 837 performs the method 550illustrated in FIG. 5B. To that end, in various implementations, thecompaction module 837 includes instructions and/or logic 837 a, andheuristics and metadata 837 b.

While various aspects of implementations within the scope of theappended claims are described above, it should be apparent that thevarious features of implementations described above may be embodied in awide variety of forms and that any specific structure and/or functiondescribed above is merely illustrative. Based on the present disclosureone skilled in the art should appreciate that an aspect described hereinmay be implemented independently of any other aspects and that two ormore of these aspects may be combined in various ways. For example, anapparatus may be implemented and/or a method may be practiced using anynumber of the aspects set forth herein. In addition, such an apparatusmay be implemented and/or such a method may be practiced using otherstructure and/or functionality in addition to or other than one or moreof the aspects set forth herein.

It will also be understood that, although the terms “first,” “second,”etc. may be used herein to describe various elements, these elementsshould not be limited by these terms. These terms are only used todistinguish one element from another. For example, a first contact couldbe termed a second contact, and, similarly, a second contact could betermed a first contact, which changing the meaning of the description,so long as all occurrences of the “first contact” are renamedconsistently and all occurrences of the second contact are renamedconsistently. The first contact and the second contact are bothcontacts, but they are not the same contact.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the claims. Asused in the description of the embodiments and the appended claims, thesingular forms “a”, “an” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. It willalso be understood that the term “and/or” as used herein refers to andencompasses any and all possible combinations of one or more of theassociated listed items. It will be further understood that the terms“comprises” and/or “comprising,” when used in this specification,specify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof.

As used herein, the term “if” may be construed to mean “when” or “upon”or “in response to determining” or “in accordance with a determination”or “in response to detecting,” that a stated condition precedent istrue, depending on the context. Similarly, the phrase “if it isdetermined [that a stated condition precedent is true]” or “if [a statedcondition precedent is true]” or “when [a stated condition precedent istrue]” may be construed to mean “upon determining” or “in response todetermining” or “in accordance with a determination” or “upon detecting”or “in response to detecting” that the stated condition precedent istrue, depending on the context.

What is claimed is:
 1. A method comprising: at a fault-tolerantenterprise object storage system configured to synthesize parity data inorder to protect stored data from loss, the fault-tolerant enterpriseobject storage system including a plurality of storage entities eachconfigured to store data on a block basis and one or more processors:writing a first object into an aggregate object that is distributedacross the plurality of storage entities, wherein a first size of thefirst object is at least an order of magnitude less than a second sizeof the aggregate object and within the same order of magnitude of ablock unit addressable within each of the storage entities; updating,based on the first object, parity data associated with the aggregateobject in response to writing the first object into the aggregateobject, wherein the parity data is stored at one or more parity storageentities; and updating a processed data end offset indicator thatindicates that the parity data for the aggregate object includes validdata up to and including the first object.
 2. The method of claim 1,wherein writing the first object into the aggregate object comprises:receiving a request to store the first object in the fault-tolerantenterprise object storage system; and writing the first object into datablocks associated with the aggregate object.
 3. The method of claim 1,wherein updating the parity data associated with the aggregate objectcomprises: synthesizing parity data for the first object; and writingthe parity data for the first object into parity blocks correspondingwith data blocks that store the first object.
 4. The method of claim 1,wherein updating the processed data end offset indicator comprises:determining the first size of the first object; and incrementing a valueof the processed data end offset indicator by the first size.
 5. Themethod of claim 1, further comprising: transmitting a message indicatingthat the first object has been written into the fault-tolerantenterprise object storage system.
 6. The method of claim 1, furthercomprising: detecting a loss of data at one of the storage entities thatstored the first object; determining, based on the processed data endoffset indicator, whether the parity data associated with the aggregateobject includes valid data for the first object; and upon determiningthat the parity data includes valid data for the first object,recovering the first object based on the parity data.
 7. The method ofclaim 6, wherein determining whether the parity data includes valid datafor the first object comprises: identifying a set of objects that havebeen written into the aggregate object, wherein the set includes thefirst object; identifying a size for each object in the set; computing asum by adding the sizes for all the objects in the set; and determiningthat the parity data includes valid data for the first object when thevalue of the processed data end offset indicator is equal to the sum. 8.The method of claim 1, wherein identifying the set of objects comprises:identifying the objects that were written into the aggregate objectprior to the first object was written into the aggregate object.
 9. Themethod of claim 1, further comprising: inserting a name of the firstobject in a database that stores names of objects that have been writteninto the aggregate object.
 10. The method of claim 9, furthercomprising: determining to delete the first object from thefault-tolerant enterprise object storage system; removing the name ofthe first object from the database; and marking data blocks that storethe first object as invalid.
 11. The method of claim 10, furthercomprising: determining whether to compact the aggregate object; andcompacting the aggregate object based on the determination to compactthe aggregate object.
 12. The method of claim 11, wherein determiningwhether to compact the aggregate object comprises: determining apercentage of data blocks in the aggregate object that have been markedas invalid; determining whether the percentage is higher than athreshold; and determining to compact the aggregate object when thepercentage is higher than the threshold.
 13. The method of claim 11,wherein compacting the aggregate object comprises: instantiating asecond aggregate object; and migrating valid data blocks of theaggregate object to the second aggregate object, wherein valid datablocks are data blocks that have not been marked as invalid.
 14. Afault-tolerant enterprise object storage system comprising: a pluralityof data storage entities, each data storage entity comprises a pluralityof data blocks for storing object data, wherein each data block isassociated with a block size; one or more parity storage entities thatcomprises a plurality of parity blocks for storing parity data; and aningest entity configured to: write a first object into an aggregateobject that is distributed across the plurality of data storageentities, wherein a first size of the first object is at least an orderof magnitude less than a second size of the aggregate object and withinthe same order of magnitude as the block size; update, based on thefirst object, parity data associated with the aggregate object inresponse to writing the first object into the aggregate object, whereinthe parity data is stored in parity blocks at the one or more paritystorage entities; and updating a processed data end offset indicatorthat indicates that the parity data for the aggregate object includesvalid data up to and including the first object.
 15. The fault-tolerantenterprise object storage system of claim 14, wherein writing the firstobject into the aggregate object comprises: receiving a request to storethe first object in the fault-tolerant enterprise object storage system;and writing the first object into the data blocks associated with theaggregate object.
 16. The fault-tolerant enterprise object storagesystem of claim 14, wherein updating the parity data associated with theaggregate object comprises: synthesizing parity data for the firstobject; and writing the parity data for the first object into the parityblocks corresponding with the data blocks that store the first object.17. The fault-tolerant enterprise object storage system of claim 14,wherein updating the processed data end offset indicator comprises:determining the first size of the first object; and incrementing a valueof the processed data end offset indicator by the first size.
 18. Thefault-tolerant enterprise object storage system of claim 14, wherein theingest entity is further configured to: transmit a message indicatingthat the first object has been written into the fault-tolerantenterprise object storage system.
 19. The fault-tolerant enterpriseobject storage system of claim 14, wherein the ingest entity is furtherconfigured to: detect a loss of data at one of the data storage entitiesthat stored the first object; determine, based on the processed data endoffset indicator, whether the parity data associated with the aggregateobject includes valid data for the first object; and upon determiningthat the parity data includes valid data for the first object, recoverthe first object based on the parity data.
 20. A device comprising: aprocessor configured to execute computer readable instructions includedon a non-transitory memory; and a non-transitory memory includingcomputer readable instructions, that when executed by the processor,cause the device to: write a first object into an aggregate object thatis distributed across a plurality of storage entities, wherein a firstsize of the first object is at least an order of magnitude less than asecond size of the aggregate object and within the same order ofmagnitude of a block unit addressable within each of the storageentities; update, based on the first object, parity data associated withthe aggregate object in response to writing the first object into theaggregate object, wherein the parity data is stored at one or moreparity storage entities; and update a processed data end offsetindicator that indicates that the parity data for the aggregate objectincludes valid data up to and including the first object.